Crews from multiple agencies gather in the encroaching pinyon-juniper forest to begin building the in-stream structures in Birch Creek, UT.Courtesy & Copyright Shauna Leavitt, PhotographerThe job of building 60 in-stream habitat structures in one week seems like a daunting task. But an energetic group of 16 natural resource managers, researchers and volunteers, finish all 60 in four days.

The crew members come from numerous agencies including the Bureau of Land Management, Utah Division of Wildlife Resources, the National Forest Service, interagency firefighting hotshots, and Utah State University.
The purpose of the project is to demonstrate how effective various in-stream structures are at improving habitat for Bonneville cutthroat trout and restoring riparian habitat on a two-mile stretch of Utah’s Birch Creek, located southeast of Beaver, Utah.

Crews from multiple agencies building in-stream structures to restore Birch Creek. Courtesy & Copyright Shauna Leavitt, PhotographerAt one time Birch Creek was rich with beaver, riparian vegetation and diverse in-stream habitat making it an ideal home for Bonneville Cutthroat trout and sage grouse.

The beaver are now gone, and the once woody riparian vegetation has been largely replaced by an encroaching pinyon-juniper forest. The creek is one narrow ditch-like channel.

According to Joseph Wheaton, Associate Professor in the Department of Watershed Sciences and Principal Investigator, “Without the help [of man-made structures or beaver dams] recovery from this type of degradation could take centuries.”

The crews built a variety of simple structures, some designed to mimic beaver dams and others to imitate natural accumulations of wood and debris jams.

An in-stream structure build from juniper branches, cobble, gravel and mud. Courtesy & Copyright Shauna Leavitt, PhotographerThe largest structures are built with an excavator. The machine pulls up large junipers and drops them in the stream so the water can run over, around and through the juniper and its root wads.
Wheaton explains, ”By putting the [Juniper} in the channel we’re making habitat for fish and at the same time raising water tables, which support a whole range of riparian vegetation and wetland vegetation.”
Another structure is the Beaver Dam Analogues (BDAs), which is a simple, cost-effective method of using posts and juniper branches then adding rocks and mud to partially plug up the deliberately leaky dams, designed to be passable to fish.

A pool forming behind a newly build in-stream habitat structure. Courtesy & Copyright Shauna Leavitt, PhotographerCrews see immediate improvements after each structure is built. New pools form, old-channels that haven’t seen water for decades begin to flow parallel to the main channel, and formerly dry floodplains become wet sponges and wetlands.

These wet sponges will release their water later in the season providing additional moisture in dryer times.
Justin Jimenez, Fisheries Riparian Program Manager with Bureau of Land Management explains why these pools are essential, “We’re working to improve the habitat for native fish by increasing the pool frequency and depth. The depth provides thermal cover.” Which is cooler for summer rearing habitat, and warmer for winter survival.
Before this project began, downstream water-rights holders were concerned about how these structures would impact water for irrigation.

In response to their concerns, Gary O’Brien, a Geomorphologist in the Fluvial Habitat Center at USU installed a common measuring device called a V-notch weir at the top and bottom the of the two-mile stretch to measure the discharge of the stream.

According to O’Brien, “once all the structures fill their pools and the system adjusts for infiltration, we expect the top and the bottom weirs to measure a relatively consistent discharge.”
By the addition of a pressure transducer in the pool behind the weirs, O’Brien will have continuous flow of data at every stage.

With these readings the ranchers can be kept up-to-date on the impact the structures are having on the water resources. The agencies have agreed to remove the structures if gaging shows the structures are negatively impacting downstream water users.

Throughout the project, UDWR, BLM and the USFS will be monitoring cutthroat trout response, and USU will be monitoring how the habitat responds and changes through time.

By monitoring the responses, managers and researchers will be able to make more informed decisions about which types and mix of structures can be most effectively used to restore similar streams cheaply across the state.